Rotary piston machine



Jan. 27, 1942. AR SOBEK l 2,270,976

ROTARY P ISTON MACHINE Filed July 6. 1938 2 Sheets-Sheet 1 l ATTORNEYS Jan. 27, 1.942. P, SQBEK 2,270,976.

` ROTARY PxsToN MACHINE Filed July e, 195e 2 Sheets-sheet 2 ATTORNEYS Patented Jan. 27, 1942 l2,27 0,976 ROTARY PISTON `MACHINE Paul Sobek,Vienna., Germany, assigner to Eric Benjamin, New York,N. Y.

Application July 6, 1913s, sei-iai No. 217,813.2y Tn Austria July 13, 1937 (Cl. B-129) 3 Claims.

` pass by each other.

` A further decided disadvantage of prior rotary engines is the fact that they cannot be regulated.

Also prior rotary piston engines, with which attempts have been made to develop relative 'speed between the pistons, have a rigidity of construction which makes it impossible to regulate their capacity. y

One object of the present invention is toprofvide a new and improved rotary piston engine, in which the above mentioned disadvantages have been overcome.

Another object is to provide a rotary piston machine whose capacity (volume or pressure) can be varied any predetermined amount, either while the machine is at rest, or While it is operating,l without the use of a special governor. This construction allows the use of a variable speed drive at all stages from complete idleness to highest speed.

In the embodiment of my invention, the rela'- tive angular velocity between the two rotary elements is a function of the angle alpha, formed by these rotary elements at a rest predetermined position of the cross-head link interconnecting said elements. With an increase of this angle alpha, the relative angular velocity of thetwo rotary elements decreases, and at an angle of 180, the two rotary elements have the same angular velocity. Thus, an idling position isattained, in which the machine used either as a suction engine, or as a power engine has no output.

"The desired adjustment of the angle alpha between the two rotary elements, can for instance, be achieved by increasing or by decreasing the distance a between the axis of rotation of the cross-head link and the axis of rotation of the rotary elements. Thus, when a, equals zero, the angle alpha reaches the aforementioned value of 180. Decreasing the angle alpha increases the capacity of the machine. Furthermore by changing the distance a, and thus changingthe angle alpha', a'regulation can be effected while the rotary elements are in motion. This can" be done manually or automatically, 'as for instance by adjustable spring pressure. The ma# chine lmay be so constructed, that with changes in thedistanceV a, corresponding regulation or displacement at the intake and outlet ports occurs.

Each'of the pistons may be in the shape of a sector of a circle.4 With this construction, the

most favorable sealing eiect is obtained, espe-- cially lwith Vmotors and compressors, and particularly when the angle of the piston sector is at least equal to the angle alpha. I have found that very favorable results can be obtained with an angle of '90 for the piston sector.

In one embodiment of the invention, the two pistons have drive connectionswith a solid and a tubular shaft respectively.

It is known, that if a piston engine is used as a compressor, difficulties in starting, large power consumption, undesirable development of heat, and other disadvantages are caused by too great a pre-compression. According to the present invention, regulation of the pre-compression is provided for.y Such regulation, can for example, be effected by increasing or decreasing the outlet ports by means of a slide valve, thus terminating the pre-compression at an earlier or later time. In another modification, a series of apertures may be arranged ,in frontA of the outlet, which maybe controlled by means of a slide valve or the like, thereby causing an earlier. or later termination of the pre-compression.

The rotary piston machine, according to the present invention, can also be constructed as a multiple-stage device, by arranging two cylinders side by side and by kproviding a cross-head link, having a double drive between them, or by arranging the second cylinder in series or tandemv with the first, thus obtaining a two-stage device in either case. The side by side arrangement may also be combined with the series or tandem arrangement to produce a four or more stage device.

In the accompanying drawings, there is shown for purposes of illustration, various forms of devices, embodying the invention, in which:

Fig. 1 is a vertical section, somewhat diagrammatic, and taken through the center of one embodiment of the present invention on line I-I of Fis- 3.

, Fig. 2 is an end view, partly in section, and somewhat diagrammatic of the device of Fig. 1, shown with the front casing wall removed,

l Fig'. E3 is the other end view, partly diagram.- matic, of the' device of Fig. l1, with the linkjadjustin'g v'mechanism "removed,

Figs. 8a, 8b, 8c and 8d are diagrams, showing respectively the various phases of an embodiment of my invention, employed as a combustion engine, and I Figs. 9 and 10 are respectively sections, some what diagrammatic, of diierent embodiments of the invention, for regulating Ythe pre-compression of a rotary piston machine.

In the form of invention shown in Figs. 1- to 5, Y

the rotary piston machine comprises acasing I, having an inlet '2, and an outlet 3. In the interior of this casing are two rotary elements, in the formy of pistonsland 5, rotating onl a commonaxis. Piston'5 is secured to a solidshaft 6, while piston 4 has adrive connection with a tubular shaft I encircling said shaft 6, and rotatablegwith respect thereto. 'Ihis piston 4 is shown'czarr-ied on the'frontal side of a disc 9, connected to the tubular shaft 'I. By means of such or similar arrangements, the pistons 4 and 5 can be moved to and fro independently of each other. vThe outer end of thesolid shaft 6 as well as the tubular shaft 'I carry cranks I I and I0 respectively. ,E'acnofthese'cranks I0 and IIhas at its end a crank lpin I2, ,which is inserted in a sliding block I3.` Both of,` these blocks I3 slide in a cross-head link I4, which is pivotally supported byv means of a pivot -I5 in a bearing I6. Instead of the sliding blocks I3, rollers or the like may beused.

The cranks 'IS and II and with them the pistons 4 andv, form an angle alpha therebetween, the value yof which depends upon the distance a between the center of the pivot l5, and the center f the shafts 6 and '1. When the link I4 is rotated about the axis of the pivot I5, the slide blocks I3, as wellfas the crank pin I2, are carried with it'. As the distance ,between the link axis and slide blocks `I 3 changes continuously, the crankslli and I l will have continuously changing angular velocities which continuously vary relatively. f

,At the starting Iposition".--A of the link I4, shown inv Fig. 4, the cranks II) and II on account of the position B-,B of rthe elements I3, "form the lsmallest possible angle. If the link is turned in the direction HofA the arrow into position l2-'A2, crank .III develops an increase and crank II ,develops a decrease .in its respective angularl velocity, and crank III begins to advance. At the link positionk .A2-.A2, the cranksv Il] and II therefore will be inthe positions B2 and B3 respectively; `at the link position A3-A3, the cranksIIl and II will be in positions B4 and B5 respectively; and at the link position A4-A4, the cranks III and |I will be in positions B6 and BI respectively-` After a half revolution of the link, the angle alpha will again be at its mini-4 mum, but the position of the cranks Iliand Il' will be reversed, that is, the vcrank I0 which was located-on the left side, will now be on theright side, and viceversa, Since the pistons rotate withthemcra'nks asfrrientioned above, and form the link as the angle between said cranks, the pistons 4 and 5 will maintain an angular relationship equal to that of said cranks.

The application of these principles to the function of a pump shows that the advance of the piston 4 in relation to the piston 5, causes an expansion of the space between said pistons, and consequently leads to a suction effect. While the` crank' I-I (Fig. 4), during va half revolution 'of the link, moves from B to B (angle alpha), piston 5 moves into the former position of pis- 'ton 4, and while crank I0 simultaneously moves fromB to B', piston 4 moves into the former position of piston 5, through an angle of "'(oe'a'lpha'). The increase of theangle alpha,

which'was-originally formed by the pistons, to

v the angle (3GB-alpha), causes an expansion of thechamber (volumetric area included by angle alpha), and accordingly creates suction. On the thesam angie at the startingposmm n n or i other side of the pistons, however, a reduction The regulation of the machine may be eiected in a very simple manner, by changing the distance a between the axis of the pivot I5 and the axis lvof the shafts E and 1. In this manner the capacity of the' pump may be changed. If the distance is decreased, the 'angle alpha vWill be increased, and the angle (S60-alpha) decreased, and the increase and reduction of space between the pistons 4 and 5 are changed vcorrespondingly. By reducing the voliuneof the working cylinder, va smaller amountis sucked in, and a smaller amount is delivered. By adjusting the position of bearing I6 with reference to 'shaft' 6, the delivery of Athe pump vmay be regulated, whilst the pumpjisrunning;` By' reducing the distance ato a2/ (Fig. 5) the'angle alpha is changed to alpha El.' If the distance a vbecomes zero, the axis of the pivot` I5V and the axis of shafts and'I kwill coincide,and alpha as well `as (360-alpha) will amount to Under these conditions, the pistons will rotate'` with constant an'gular'velocity, so `that there is no suction'and ,no delivery, and the machine simply idles. 'Thusy by adjusting the Vbearing I6, the deliveryrnay be regulated from Zero to a. maximum, even while the pump is' in motion. This regulation may Ybe performed 'manually or automatically ,inresponse to `the output pressure, andthrourgh the use of 'spring pressure. If the pre-adjustedmaximum pressure in the pump is exceeded`,'th e angle "alpha-'between the pistons v'is changed, and thev link will change its position in accordance with a set spring pressure Inthe case of large pumps an adjustable hydraulic backpire'ssure mayV advantageously be used instead of spring pressure. ,A N 1 In Fig. 1,' manually operatedvmeans aresomewhat diagrammatic'ally shown, for adjusting the position of the pivotal supportlof the link I4v with respect to the axis'of the shafts 6 and IL In the speciiic form shown,this means includes a screw member I1, threadedl into a-stan'dard I8, and havingits upper end supporting the bearing I6.v Fixed-to this screw'member` I lisa collarf I9, having a series fof spaced holes on its periphery-for receiving va suitable turning tool 2.0.' .The rotation-of this'collarV I9 causes a corresponding Vrotation of the screw/member, ll,and effects the required adjustment of thebearing I6.`l` e,

Inasmuch as in an adjustable pump.' the position of the pivot is changeable, the shaft 6 which in that case extendsthrough thecover lla (Fig. 1, ,dotted` lines) is used as adrVIlg shaft. The link i4 in thisr case, provides for the connection between the piston5 and shaft 6. 4Simultaneously with .the change in the distance a, the position 'or area of the openings of the ports or both maybe changedjthrough a connection with the link bearing. The possibility of a simple'regulationiof the rotary piston machine by merely shifting the link bearing I S during operation, permits the use ofthe machine as a variable` hydraulic gear.r VThis-is accomplished by connecting two pumps in series, one of them being driven as a -primary element (generator) and the other as a secondary element (hydraulic motor) It isepreferable to combine both parts structurally into one unit. If reverse motion of the machine is desired, the pivot I5 must be moved through and beyond the axis of shafts 6 and 1r. Then the distance between the two axes will govern the speed of the reverse motion. In such case, the intake and outlet aperture will necessarily change their respective functions.`

In Fig. 6 the intake p orta and outlet port 3c are substantially widewat the periphery of the casing, and the ends of-.the pistons 4a vand 5a have segmental port sealing sections of substantion of the link pivot and with the aid of-fa suiteblegovernorf. j I Furthermore, the rotary piston ,elgine according Ato the presentinvention may alsobe usedfor internal combustion ,engines with. particularly favorable-results, Figs; 8a, 8b, 8c and 8d show the sequenceof the phases in the case of a gasoline motor. e, The different phases are shown, as the pistons 4c and 5c start to diverge, and as they end theirl approaching movement, va cycle y corresponding toa half revolution of the link.

tial length corresponding somewhat to the Width of said ports. Between the pressure and the suction side a proper sealing of the ports is thereby provided. In this construction also, the piston 5a lags in relation to the piston 4a. Owing to the simplicity of construction, high temperatures need not be feared, and usual cooling and ventilation methods may therefore be applied in the ordinary way. The construction of Fig. 6 is particularly adapted for use as a variable hydraulic gear.

A pronounced drawback of compressors is their relatively large size compared to their capacity. By means of the present invention, especially as embodied in the vform shown in Fig. '7, this drawback is largely overcome. In this embodiment of the invention, the pistons 4h and 5b are each in the form of a sector of a circle, and rotate in a casing lb, having an intake port 2b and a discharge port 3b. By reason of the fact that thek relative angle of the pistons can be reduced to practically zero, maximum discharge is assured, and the above mentioned drawback is overcome. This construction aiords exceptionally good sealing possibilities which are not applicable to the ordinary piston compressor. On account of this, and also owing to the favorable cooling possibilities, extraordinarily high pressures can vbe obtained. Multiple-stage construction is also possible. Furthermore, the pistons4b and 5b may be equipped with internal cooling. Thus by the `rocating piston engines.

In the phase shown in Fig. 8a, the exhaust is terminated,.with subsequent starteof `suction in the spaceC `between the, pistons dcand 5c. In the space D between the pistons 4c and 5,cth e explosion is terminated and-,exhaust begins- In the phase *shown in Fig. 8b, the vexhaust kis terminated and suction beginsin'the space Dbetween the pistons 4c and 5c. The suctionis terminated and the compression starts in space. C. In the phase shownein Fig. 8c,y compression is terminated and explosion .begins in, space C. Suction is terminated 'and compression begins in Spae D. w f

y Inrthe phase Vshown inl Fig.8d, compressionfis terminated and explosion starts in space D. EX-gplosion is terminated and ,exhaust begins in space C. y 1,.,

i The inlet and exhaustgports mayeitherV Control themselves or known systems mayv be applied. They may be controlled by the piston peripheries oer-through theuse of knownsystemsr of valve control. The .useof the rotary pistonmachine accordinghto thepresent invention affords again the possibility of regulating the changes of compression in a most simple manner, such as could not be attained by the hitherto known methods, merely by shifting the link pivot. As the machine according to the present invention does not contain parts which pass by one another, the possibilities of packing are as favorable as in recip- The invention is especially applicable for airplane engines. The double-action of the engine, its favorable operativeconnection, and its simple, effective cooling, aord the possibility of producing for the same capacity much smaller and considerably lighter engines'than was hitherto possible withreciprocating pistons.

Fig. 9 shows a construction for regulating too high a pre-compression. This construction comprises a slide 2| arranged at the outlet 3d in a recess 22 ofthe casing Id, in which rotate the pistons 4d and 5d. This slide maybe shifted in varying degrees in the direction of the arrow F. In this way the pre-compression may be terminated earlier or later, and the desired regulation may be obtained either manually or automatically.r

' In the construction shown in Fig. 10, the recess 22-forms awall 23,.having a series of holes 24, controlled by a slide 2|al in said recess. This slide 2da. can be'shifted in both directions as indicated by the arrow F, to cover or uncover the holes 24. Thus with the aid of said holes 24, the pre-compression can be terminated earlier or later, depending on the number of said holesy covered by the slide Zla.

Although in the form of the invention shown in Figs. 9 and 10, the slides 2| and 2|a are disposed for control of the discharge ports 3d, itV

must be understood that a similar arrangement maybe provided for the inlet ports 2d.

The pistons in the constructions of Figs. 1 to 6 are shown somewhat diagrammatic for the purpose of illustration, but it must be understood that these pistons may be sector-shaped, as show in theconstructions of Figs. 7 to 10.

The application of the rotary piston machine, according tothev presentinvention, is not limited to the uses describediabove-- It is possible to use such machines rin'a number of other fields without departing from the principle ofthe rotary pistons according to the invention. f It must beunde'rstood that the pistons in the construction of Figs. 7 to 10 may be hollow if desired l l VIt must also be understood that blocking means may be provided for preventing the rotation of the pistons in undesired directions. f

As many changes could be made in the above construction, and many apparently widely different embodiments of `-this invention-could be made without departing from the scope thereof, itis-intended that all matter contained in the above description or shownin the accompanying drawings shall be interpreted as illustrative and not in .a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is:

l. Arotary piston machine comprising a working chamber having an inlet and an outlet, a pair of rotary pistons coaxial with said chamber and operable therein, a pair 'of arms outside of said chamber and connected to said pistons, a rotary cross-head outside of said chamber and engaging said arms, a'bearing for said cross-head outsidelof said chamber, the axis of said bearing being eccentric' in respect to the vaxis of said pistons, whereby upon rotating said cross-head differential movement is imparted to said pistons, and means for adjustingA the position of s aird bearing radially with respect to the axis of said pistons to vary the extent of differential movement between said pistons.

2. A rotary piston machine having an annular working chamber having an inlet and an outlet, a pair of pistons in said chamber and rotatable about the axis of said chamber, a pair of concentric vshafts connected to said pistons and extending to the exterior of said chamber, a pair of arms connected to said shafts outside of said chamber, a third shaft eccentrically disposed in respect tor said chamber and having a slotted cross-head engaging said arms, and means for adjusting the position of said last mentioned shaft in a direction radial of said chamber.

3. A rotary piston machine having an annular working chamber having an inlet and an outlet, a pair of pistons in said chamber and rotatable about the axis of said chamber, a pair of concentric shafts connected to said pistons and extending to the exterior of said chamber, a pair of arms connected to said shafts outside of said chamber, a third shaft eccentrically disposed in respect to said chamber and having a slotted cross-head engaging said arms, and means for vertically adjusting said last mentioned shaft radially of said chamber to thereby vary the eccentricityv of the latter and to Vary the extent of differential movement of said pistons.

y I PAUL SOBEK. 

